Support custom terrains being overwritten (#1376)
Support custom terrains being overwritten (#1376)


Zarel/Pokemon-Showdown-Client,sirDonovan/Pokemon-Showdown-Client,sirDonovan/Pokemon-Showdown-Client,sirDonovan/Pokemon-Showdown-Client,Zarel/Pokemon-Showdown-Client,sirDonovan/Pokemon-Showdown-Client,Zarel/Pokemon-Showdown-Client,Zarel/Pokemon-Showdown-Client